March 02, 2026-
Ocugen, Inc. has announced completion of enrollment in its Phase 3 liMeliGhT clinical trial evaluating OCU400, a modifier gene therapy candidate for retinitis pigmentosa (RP). Topline data from the one-year study are expected in Q1 2027 and are anticipated to support a Biologics License Application (BLA) filing in 2027. The European Medicines Agency has also confirmed acceptability of the U.S.-based trial for a future Marketing Authorization Application (MAA).
The Phase 3 liMeliGhT trial enrolled 140 patients randomized 2:1 to receive OCU400 (2.5×10¹⁰ vg per eye, 250 µL) or serve as untreated controls. The study includes both RHO mutation and gene-agnostic arms and spans early- to late-stage RP, including pediatric patients aged three years and older. The primary endpoint is the 12-month change in visual function measured by luminance dependent navigation assessment (LDNA), a mobility-based functional endpoint designed to detect clinically meaningful changes in lux level performance.
OCU400 is an AAV-based modifier gene therapy built around the nuclear hormone receptor NR2E3. Rather than replacing a single mutated gene, the therapy is designed to reset dysfunctional retinal gene networks and restore cellular homeostasis across multiple RP genotypes. RP is linked to mutations in more than 100 genes, and currently approved gene replacement therapies address only a small subset of patients.
According to company leadership, the broad inclusion criteria and mutation diversity in the Phase 3 study are intended to validate OCU400’s gene-agnostic mechanism of action. Investigators emphasized the unmet need for therapeutic options for the approximately 98% of RP patients who are not eligible for currently approved single-mutation gene therapies.
The enrollment milestone follows encouraging long-term Phase 1/2 data. At three years, evaluable subjects demonstrated consistent visual function benefits, including an approximately two-line improvement in low-luminance visual acuity (LLVA) across multiple mutation types. Eighty-eight percent (7/8) of treated eyes showed improvement or preservation compared with untreated fellow eyes, with durable safety and tolerability and no new treatment-related serious adverse events.
With Phase 3 enrollment complete and supportive long-term data in hand, Ocugen plans to initiate a rolling BLA submission in the third quarter of 2026, positioning OCU400 as a potential one-time AAV gene therapy option for a broad RP population.
